I have good news and bad news. The good news is that Asteroid 2012 DA14 is not going to hit Earth. The bad news is, even if it were going to hit Earth, it wouldn't happen until February 15th so you will still have to buy a Valentine's Day gift.

Asteroid 2012 DA14 was discovered last year, on February 22nd by astronomers at La Sagra Sky Survey observatory near Granada, Spain. Because it is small in size it was only noticed after it had flown past us, but astronomers knew then it would be back, this time much closer.

How close? 24,000 KM close. As in the distance of some satellites. That means you will be able to see it with binoculars.

Why didn't they notice it before? There are 500,000 of things this size zipping around us in space and it's only 150 feet in size. It turns out this asteroid jumps in and out of our path every year, it even has an orbit similar to ours, a period of 366.24 days. Once astronomers detect it the first time, calculating the path is not so difficult.

In case you missed it last year. Credit:ESA

If you are in Europe, it will have a maximum brightness of about 8 stellar magnitudes when rising above the horizon and will approach Earth from the south. It will rise above the horizon in Virgo, then move northwards left of the constellation Leo. Two hours later it will be seen in the Little Dipper and by morning will have crossed half of the sky but at magnitude 13 you will need a telescope to see it at that point.

This isn't going to hit, but what could an asteroid that size do if it hits? Quite a lot, a sobering thought since, as I mentioned, there are 500,000 objects this size to track just close enough to think about. The June 20th, 1908 event at Tuskunga was a 300 foot meteor and it had an explosion bigger than the atomic bomb used at Nagasaki in World War II, thousands of square miles of devastation.

Astronomers look for everything happening out there but a group called B612, founded in 2001 by a former astrononaut wants to 'make an impact' (get it??) just in smaler destructive events - the kind that won't wreck a planet but would wreck cities. They say that the technology to deflect a life-altering asteroid is there right now - more "Armageddon" and less "Deep Impact" if you need disaster movie context - but it needs a devoted monitoring effort. They are raising money to design, build, launch, and operate an infrared space telescope solely for the purpose of tracking the hundreds of thousands of smaller asteroids that are not tracked with current telescopes.

Sentinel proposed field of view. Credit and link: B612

Since we know this goes by us about twice a year, at varying distances, is there anything to worry about? Not for at least the next century but one fun aspect is that we get to see a large experiment in gravitational change in a more manageable way than monitoring the moon or anything really large. 100 years from now the probability of an impact is still only 8.0e-09,which is a 1 in 125,000,000 chance of getting hit. That means it is 99.99999920 % certain that if you are still alive in 2112 to see 2012 DA14 approach Earth, you will also be alive to watch it disappear from view again.

A debated claim is that this kind of event wiped out the dinosaurs - evidence shows extinctions accelerated right after that - and without dead dinosaurs we wouldn't have had the rise of placental mammals like us, so sometimes good things results from bad things. But dinosaurs did not have a space program. Or Bruce Willis. Be sure that if anything world-ending from space is happening any time soon, you will read about it here well in advance.

Space is a vacuum. What would it take to destabilize our atmosphere. I mean; the bible says the heavens will fail like a scroll rolling up (something like that anyway). So a direct hit is not necessary. I'm surprised they let all that garbage float around our planet stirring things up. Bit by bit we are likely losing our atmosphere. A meteor traveling thru though; could change things rather quickly. Though I guess no one has thought of that angle. Could be worse though. At they they told the public a few days before it happened. I doubt they'd inform the public if something bad where coming.

As it turns out, Earth -is- losing its atmosphere, bit by bit. The itty-bitty molecules of air have a calculable distribution of velocities. Some velocities are rather small, some rather large, and most are in-between those two extremes. There's a relative few which are traveling in excess of local escape velocity from Earth. At the extreme upper-atmosphere there's a long mean-free-path between molecules, so long that the speediest ones suffer no collisions to deter them and they leave the vicinity of Earth altogether, forever.

Incidentally, an asteroid the size of an apartment building isn't enough to strip Earth of its envelope of air. Much bigger ones have hit lots of times in the past; there are large craters peppered all over Earth's surface. Life has thrived for the most part just the same. The cosmic interloper at Tunguska in 1908 fell millions of trees and was witnessed by human eyes. We're still breathing.

So, what about the doomsday prophets in the headline? I have deep participation in this area, and I'm not aware of any "doomsday prophets" who think any different than the scientists regarding this asteroid. Seeing as they weren't mentioned at all in the article, perhaps change the headline??

"Thousands of square miles of devastation"---the TUNGUSKA event gets bigger every time i read about it!! (in a DA14 context anyway). LOL... fact is, that event is still of unresolved cause; a "300ft diameter" anything is pure speculation. And if you bothered to run the parameters of DA14 through the Impact Earth Effects simulator (http://impact.ese.ic.ac.uk/ImpactEffects/), you would see that NASA picked a perpendicular impact scenario on which to base its predictions of a putative "regional devastation" effect of an impact of this object. In reality the likest impact angle is 45degrees...and when this one modification is made to the parameters the impact (air blast actually) goes from a double digit psi overpressure scenario to more realistic (and much less sensational) 2.4psi. BIG difference--and Tunguska it certainly isn't--not even close.

Well, "conspiracy" theorist or not, I do know that Nasa has made some spectacularly bad math errors in the past. Look up "Mars Climate Orbiter" sometime. That's the one were Nasa spent over 250 million dollars, reassured top politicians in both their own organization and Congress that this was the coolest project since the Moon landing and therefore worth funding, and then got to watch the entire orbiter crash on the surface of Mars in a highly public gaffe. Why? Because someone forgot to change English measurement to Metric. I've also now seen TWO Space shuttles crash and burn in my time. The first one because someone at Nasa decided that no one would be stupid enough in another department at Nasa to design rubber O-rings that would LEAK explosive fuel on the space shuttle, so why wait just because it got cold the night before? It's a damned super space machine isn't it? No pitiful O-ring is going to stop us! Or in the second disaster when the tiny pieces of Styrofoam were shown hitting the heat shielding, and everyone in Nasa agreed that "styrofoam is soft, it can't damage heating tiles". Until AFTER the disaster when they shot styrofoam at orbital escape velocities and watched it blast thru multiple layers of heat shielding like a hot knife thru butter. Objects at high speed can have different properties--ie soft when thrown as a Nerf ball by a kid, and harder than a cannon if moving at 40,000 KPS.

Now how could these types of errors at Nasa happen? If you have 12,000 people working on the project, double and triple checking each others work, how does this happen? Because no one IS double and triple checking. A department gets the assignment, in this case to plot the course of an asteroid, and that department plots it. The actually plotting of the course could be handed to the 1st year astronomy intern to type in the course, speed and other data and hit the computer computational button. Then the rest of Nasa--not having plotted the course themselves--takes this departments work as gospel and runs with it, releasing reassuring press notices and letting the public know that "Yes, the space shuttle is safe", "We are going to map the climate of Mars" and "The Earth will not be struck".

One thing that I have heard happening before is for a course to be plotted, but no external variables factored in. If for instance the asteroid was passing Jupiter, you wait until after it passes Jupiter, then plot the course. What Jupiter will do to its course is unknown, or knowable only within a certain range, because gravity can fluctuate based on position and movement of both objects to each other. And at 500 billion miles away, it's sometimes hard to estimate in objects actual speed and position. Imagine that.

So the course of this object may have been plotted with the idea that it will approach Earth and not factoring in if any other object will influence it. If you plot it before, you stand the chance of looking like a putz in front of your boss if for some reason the object is more heavily influenced by Jupiter than appeared likely in the computations, or if it strikes another object unknown to any measuring instruments we have, and goes off course. Then you look like an idiot in a field of people who do not suffer the perception of idiocy lightly.

Is there a spatial object that could impact the course of Asteroid DA14 2012 that might have been ignored in computations? The object I question which I'd like to hear more about from Nasa is the Moon's influence on the object. The Moon currently will be, I have been told, in a position where the asteroid will pass it during it's orbit. The Moon will be to the "left" of the asteroid. This asteroid will pass on the Moon's right side, and then 24 hours later on the Earth's right side as well. So for the next 4 or 5 days the Moon's gravity MAY--and I have to stress that--have an influence on this object by pulling it to the "left" in its course. If the Moon's gravity can move the object by a less than one percent difference when the object is 1 million miles away then the 17,200 miles to the right where the object is suppose to pass, missing Earth, could become a much smaller ratio, or it might even mean the object strikes Earth. I would remind everyone that this object is going to be passing within satellite orbital distances. This means automatically that it will be in the Moon's gravity field. Can the moon exert an influence? Well it manages to move billions of tons of water on the Earth every day, and causes the ocean to "bulge" on the side that is facing the Moon. The Earth is spinning. This asteroid is not. It is being constantly influenced over the next few days as it approaches our planet. Enough to move it the required distance to hit us? I don't know. But I'd feel better if some journalists in their respective fields would get up off their asses and stop reassuring the public in Kevin Bacon fashion that "All is well!!!!!" when the reality is that a rock capable of destroying one or more of our largest cities and producing an explosion twice as powerful as the biggest atomic bomb ever exploded is coming damned close. It's worth asking a few extra questions of officials to make sure. Hell you might even scoop a story if you got them to recalculate their figures. Will that happen? No. Journalists don't investigate now. They just reproduce what they are handed.

1) Collect money
2) Phone up observatory and get ephemerides of your Asteroid Of Interest
3) Hire a couple of boffins and programmers ask them to run a range of simulations on a minicomputer
5) ????
6) Get your DOOMSDAY PROBABILITY SPREAD!!

There are many things in the universe that are unclear, but orbital mechanics ain't one of them, Mister. Since about 1687.

Hi Hank,
Very illuminating article. I'm so over those who sensationalize doomsday. I suspect that if it occurs, it will take them as much by surprise as most of us since we would not be informed of it by the powers that be.

But I have a question: I'm wondering, after seeing the Sentinel graphic, if it is true that we are only looking along the orbital plane of the solar system for rocks that can hit us? I mean, can't objects of high enough mass and speed hurtling through space approach our planet from above and below that plane?

your are talking no sense. \you are just guessing the asteoid behaviour in space. even if it doenst hit, it doesnot make your expanation correct. you people dont know anything about , as you satellites are orbiting near earth. just some fools writing their imagination. remeber books and lessons you read are findings of some person. which can have 50\;50 possibility of wrong. \As i know science is also a belief . you belive on what someone has discovered. some people believe on what god has said. so they are not wrong..

When I read the title, I expected Asteroid 2012 DA14 to be colossal. A size of 150 ft. would still cause a rather large impact, but nowhere near “doomsday” standards. Even compared with the new, smaller estimate of the dinosaur-killing meteorite (4-6 km), DA14 is minuscule. Even in the 1 in 125,000,000 chance that we we’re struck in the coming century, the worst case scenario is that impact is in the center of a major city: tragic, but not mass extinction.

I do have a question, though. If, on the off chance Asteroid 2012 DA14 did enter deep enough into Earth’s atmosphere, with a size of only 150 ft., would it not disintegrate before impact? Most of the 500,000 things of similar size around us burn up in the atmosphere on a regular basis. Why was there such a big fuss about this one object? What made/makes it of interest? Or is it just media hype?

I'll be using two of the slooh.com robotic telescopes to track the asteroid throughout the night. We'll also have another telescope feed joining us from Arizona on one of the later shows. Bob Berman of Astronomy magazine will be guesting on the shows.

Because of its relative proximity to Earth, we'll have to track it as a satellite rather than an asteroid - this is because its apparent rate of motion changes from second-to-second. This means the telescope mount has to constantly change its slewing speed.

Thank you for your post about DA14 and the links to the B612 Foundation and Sentinel Mission. We appreciate the important discussion about Near Earth Objects, the threat they pose to Earth, and our ability to find them before they find us.